1. Field of the Invention
This disclosure relates to a display, and particularly to a buffer element and a manufacturing method thereof, a backlight module, and a display device.
2. Description of the Related Art
Backlight module is one of important components of a liquid crystal display device. A crucial part of the backlight module is a light guide plate.
Currently, most of the light guide plates are made of polycarbonate (PC) and polymethyl methacrylate (PMMA) which each has a small thermal conductivity. Since a backlight source such as a LED light source releases heat in operation, the light guide plate will be expand and deformed when heated by the accumulated heat. However, since the light guide plate is constrained by a member for controlling a size such as a frame, it is difficult for the light guide plate to be deformed and extended in a direction of a plate plane. Therefore, the light guide plate will be warped and thus parts such as optical film and sheet will be warped so that normal displaying of a display device is adversely affected and picture quality is reduced.
Furthermore, currently the entire backlight module trends to thin so that a thickness of the light guide plate is also decreased continually. The thickness of the light guide plate is often decreased up to 0.2-0.4 mm. Therefore, the light guide plate is warped more seriously when heated.
For the above problem, a current method for addressing bad thermal stability of the light guide plate in the backlight module is mainly to reserve a gap as an expansion space for the light guide plate in the backlight module, so that there is a space for the light guide plate to be extended therein after being expanded when heated. In this way, the warp of the light guide plate is alleviated.
Such a design alleviates the problem caused by thermal expansion of the light guide plate to a certain degree. However, since the light guide plate is positioned by a member such as a frame, a gap needs to be reserved for the light guide plate in the prior art. In this case, because of existence of the gap, the light guide plate is movable in an up-down direction and a left-right direction so that the optical quality of the backlight module fluctuates and thus the quality of the backlight module is reduced.
In addition, if the backlight module is vibrated during transportation and when suffering an external force, the backlight module and the other parts in the backlight module will collide with and scratch each other since the light guide plate is in a movable state inside the backlight module. As a result, the quality of the backlight module is adversely affected.